document.write( "Question 31632: 3) Suppose you throw a baseball straight up at a velocity of 64 feet per second. A function can be created by expressing distance above the ground, s, as a function of time, t. This function is s = -16t2 + v0t + s0
\n" ); document.write( "• 16 represents 1/2g, the gravitational pull due to gravity (measured in feet per second2).
\n" ); document.write( "• v0 is the initial velocity (how hard do you throw the object, measured in feet per second).
\n" ); document.write( "• s0 is the initial distance above ground (in feet). If you are standing on the ground, then s0 = 0.\r
\n" ); document.write( "\n" ); document.write( "1. How long will it take to hit the ground?\r
\n" ); document.write( "\n" ); document.write( "2. What is the maximum height of the ball? What time will the maximum height be attained?\r
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Algebra.Com's Answer #18279 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
Using the given function:
\n" ); document.write( "\"s%28t%29+=+-16t%5E2+%2B+%28vo%29t+%2B+so\" and substituting vo = 64 ft/sec. and so = 0
\n" ); document.write( "\"s%28t%29+=+-16t%5E2+%2B+64t\" Set s(t) = 0 and solve for t to find the time at which the baseball will return to the ground.
\n" ); document.write( "\"0+=+-16t%5E2+%2B+64t\" Solve for t. First factor out a t.
\n" ); document.write( "\"0+=+t%28-16t+%2B+64%29\" Apply the zero products principle.
\n" ); document.write( "\"t+=+0\" This is the initial condition when the height, s = 0.
\n" ); document.write( "\"0+=+-16t+%2B+64\" Add 16t to both sides of the equation.
\n" ); document.write( "\"16t+=+64\" Divide both sides by 16.
\n" ); document.write( "\"t+=+4\"Secs.
\n" ); document.write( "1) The ball returns to the ground in 4 seconds.\r
\n" ); document.write( "\n" ); document.write( "The maximum height of the ball can be found by finding the location of the verttex of the parabola that is represented by the original quadratic equation\"s%28t%29+=+-16t%5E2+%2B+64t\"
\n" ); document.write( "The t-coordinate of the vertex is given by\"t+=+%28-b%29%2F2a\"
\n" ); document.write( "The a and b come from the standard form of a quadratic equation\"ax%5E2%2Bbx%2Bc=0\"
\n" ); document.write( "In this problem, a = -16, b = 64, and c = 0\r
\n" ); document.write( "\n" ); document.write( "\"t+=+%28-64%29%2F2%28-16%29\"
\n" ); document.write( "\"t+=+%28-64%29%2F-32\"
\n" ); document.write( "\"t+=+2\"Secs. This is the time at which the baseball reaches its maximum height.
\n" ); document.write( "To find the maximum height, substitute this value of t into the original equation and solve for s.\r
\n" ); document.write( "\n" ); document.write( "\"s%282%29+=+-16%282%29%5E2+%2B+64%282%29\"
\n" ); document.write( "\"s%282%29+=+-64+%2B+128\"
\n" ); document.write( "\"s%282%29+=+64\"Feet. This is the maximum height attained by the baseball.
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